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Why were pandas merges in python faster than data.table merges in R in 2012?
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It looks like Wes may have discovered a known issue in data.table when the number of unique strings (levels) is large: 10,000.
Does Rprof() reveal most of the time spent in the call sortedmatch(levels(i[[lc]]), levels(x[[rc]])? This isn't really the join itself (t...
How to apply specific CSS rules to Chrome only?
...https://jeffclayton.wordpress.com/2015/08/10/1279/
/* Chrome, Safari, AND NOW ALSO the Edge Browser and Firefox */
@media and (-webkit-min-device-pixel-ratio:0) {
div{top:10;}
}
/* Chrome 29+ */
@media screen and (-webkit-min-device-pixel-ratio:0)
and (min-resolution:.001dpcm) {
div{top:0...
JavaScript: How to pass object by value?
...var key in obj)
temp[key] = clone(obj[key]);
return temp;
}
Now you can you use like this:
(function(x){
var obj = clone(x);
obj.foo = 'foo';
obj.bar = 'bar';
})(o)
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Why use iterators instead of array indices?
...is a concurrent modification to the structure you are accessing, you will know about it. You can't do that with just an integer.
– Marcin
Oct 21 '08 at 22:25
4
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What is the Git equivalent for revision number?
...es, how can git reasonably assign a sequential revision number? A has no knowledge of B before they push/pull each other's changes.
Another thing to look at is simplified branching for bugfix branches:
Start with a release: 3.0.8. Then, after that release, do this:
git branch bugfixes308
This...
How to run travis-ci locally
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Run the attached client
docker exec -it $BUILDID bash -l
Run the job
Now you are now inside your Travis environment. Run su - travis to begin.
This step is well defined but it is more tedious and manual. You will find every command that Travis runs in the environment. To do this, look for for...
Entity Framework 4 vs NHibernate [closed]
...rea Thats, great news, I didn't expect this, browsing EF source code right now, pretty interesting reading.
– Alex Burtsev
Aug 1 '12 at 18:15
2
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Printing a variable memory address in swift
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Swift 2
This is now part of the standard library: unsafeAddressOf.
/// Return an UnsafePointer to the storage used for `object`. There's
/// not much you can do with this other than use it to identify the
/// object
Swift 3
For Swift ...
C++ Build Systems - What to use? [closed]
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You can use Gradle now: https://docs.gradle.org/current/userguide/native_software.html
This seems to have matured quite a bit in the years since I originally posted this. The page saying that the project is "incubating" has disappeared, but I ...
Read stream twice
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I know this comment is out of time, but, here in the first option, if you read the inputstream as a byte array, doesn't it means that you're loading all the data to memory? which could be a big problem if you're loading somethin...